Boat.



W. B. MOTHERAL.

BOAT. APPLICATION FILED FEB. 27, 1908.

Patented Oct. 6, 1908.

2 SHEETSSHEET 1.

UNHED s ATEST PATENT i I E- i WILLiAM B. MOTHERAL, or WASHINGTON, nrs'rmc'r/ OF, COLUMBIA.

- IBO'AT.

To all whom it may concern:

Be it known thatI, WILLIAM;B. MOTH- RAL, a citizen of the United States, residing at Washington, inthe District of Columbia,

5 have invented certain new and-useful Improvements in Boats, of which the-following isa specification;

grovements in the shape of the hull and in etails of construction of boats of thatparticular character shown informerpatents issued to me, formed with wedge-shaped hulls and wherein air is forced under the boat to form a cushion between'its-bottom and 5 the water to facilitate; its propulsion, whereby such a boat is rendered more perfect in I its construction, and improved results may be attained, all as willbe hereinafter more .fully described and claimed. f .20 Referring to the accompanyin drawings which are made a art hereof an" on which similar referencec aracters indicate similar arts, Figure 1 is the under side plan of'the hull of one of my boats embodying said im- I provements, Fig. 2 a central longitudinal sec-Y tion through the same-Figs. 3, 4'and 5 detail views illustrating features of constructionon an enlarged scale, and Figs. 6 to 11 inclusive cross sections through the hull of the boat at the several points indicated by the several .dotted lines in Fig: '1, to show more clearly the particular shape of the bottom and sides of said hull.

In said drawinlgs the portions marked A repiresent the hu -of the boat, B the propeber shaft, and C an air-supply main or tu i e. The particular shape of the hull A will be bestunderstood by careful exam-inatio of 40 1 in-connection with the cross sectio s 6 i .to 11; It may bestated that'the bottom of the boat is curved in cross section, said bottom, asibounded by the lines m-a: in Fig. 1,

- f beingin the form of a section taken oflon'e .45 sideof a perfect cone, the radius of the circle or curvature increasing regularly from the bow towards the stern, the'sides of the hull, beingi'thes ace between the line x and the linez cated in Fig. 1, are also curved,

curvature being the greatest at a point near the stern, as shown in Fig." 6, and gra dually fiatteningtoward' the bow until at the bowof theb'o'at the sides are flat or plain, as showninFig, '11. At each side near the stem the bottom is formed with portions'a. slightly bulged down, or curved downwardly Specification of Letters Patent hpplication filed February 27, 1908. Serial No. 4 18,058.

' My said inventlon consists 1n certain 1m:

and additional the bow; It will beunderstood, of course,

Patented OctL'G, ieos.

from thestraight'level of said sides. I means the boat is not only steadied on its bottom vbut as .its speed increases these bulged-down portionshave .a tendency to cause thestern of the'boat to rideover the Water, raising it so that its draft decreases as By this its speed increases, and also serve to keep thev bow of the boat from rising unduly. The general shape of the hull just described serves to cause the boat to rise upwardlyin the 'water as its speed increases and to cause it in a large measure to skim,-or glide, over the '-water,wh en under great speed, thus enabling unusual speed to be attained ata comparatively .small expenditure of ower. bottom of the boat is perforate alon lines 7 parallel with its sides,'as shown'most-c early in Fig. 1, and the erforations are protected by deflector shiel s a. also formed ,wed e-. shaped and curved downwardly from t e bottom of the boat, thus being also in the.-

form of conesectibns, and one located im- 7o The mediately in front of each erforation. The

formof said shields is sue that inpassing over the water each shield serves to divide the water immediately in front of the adj acentperforation and form a channel to re ceive' the air as well as to cause a suction to' draw the water downwardly, as will bepresently described. I have shown two-rows of such holes alon' the entire length of the boat lloles'between said rows near that as: many rows asd'esired or found advantageous may be used and any other suitable arrangement employed.

The propeller shaft BiS j mounted in'suitable bearings being provided with a propeller b on its outer end and connected with an engine B at its inner end conveniently located within the -boat. The propeller and engine are,:or may be,'of any suitable construction and arrangement and are not 'particularlyfshown, bemgno part of. the

present invention,

- The air-tube, or main, 0 extends horizontally between the deck A and the bottom ofthe boat, being provided at its rear end-with the upwardly :extending branch C the top for end of which is provided with a valve'c.se-.-

cured thereon. by means of a ivot c. A "small supply lpipe -c connects ea'c of the" perforations in t e bottom of the'boat under the shields a with said air-tube, or main In operation, th boat being driven rapidly through the water,.its cone-shaped bottom is very slight, whilethe suction caused by the boat gliding over the water will draw the air 5 through pipes C, C and c by suction and discharge it under the boat behind the shields 2 0 secure by Letters Patent, is:

1. A boat comprising a hull'the bottom of which is in the form of a section of a cone, having bulged-down portions on each side near the stern and the sides of. which are formed curved at the stern and gradually flattened from the stern to the bow, substantially as set'forth.

. 2. A boat comprising a hull formed wedgeshaped with its bottom inthe form of a sec- 3.0 tion ofa-cone and its sides curved outwardly at the sternand gradually decreasing .in curvature untilthey run into flat portions at the bow, substantially as set forth.

A boat comprising a hull the bottom whereof is curved in cross section, the curvature gradually decreasing from the bow toward the stern and formed with'bulged-down portions on each side near the stern and having sides curved outwardly near the stern 40 and deqleasingin curvature from the stern toward the bow, substantially as set forth.

stern, perforations in said bottom, an airsupply system connected with said perforaand taperingly curved sides will cause it'to gradually rise out of the water until its draft a, causing a thin layer or cushion of air to be vention, what I claim as new anddesire to 4. A boat comprising a hull the bottom of tions, and deflectors in the form of a secti on of a hollow cone attached to the bottom of said boat immediately in front of each of said perforations with the point of the cone towards the bow of the boat, substantially as set forth.

- 5. A boat comprising a hull formed with perforations in its bottom, an air-supply system. connected with each of said perforations, a valve controlling the flow of air through said supply system, and a deflector shield on the bottom of said boat adjacent to the front side of each of said perforations, each of said shields being in the form of a section of a hollow cone with the point of the cone toward the bow of the boat, substantially as set forth.-

. 6. The combination, with a boat having a perforated bottom and provided with an airsupply system, of a deflector on the bottom of said boat adjacent to the front edge ofeach of said perforations and made in the form of boat, substantially as set forth.

. 7. A boat comprising a hull formed wedge shaped and having a bottom in the form of a section of a cone and sides curved outwardly at the stern and gradually flattening toward the bow, an air-supply system in said heat connected with series of perforations in the bottom thereof, and a wedge-shaped deflector on the bottom of said boat adjacent to the front edge of each perforation with the narrow part of said deflector arranged toward the bow of the boat, substantially as set forth.

i In witness whereof, I, have hereunto set my hand and seal at \Vashingto'n, D. G, this a 26th day February, A. D. nineteen hundred and eight.

WILLIAM B. MO'IHERAL. [it

Witnesses 1 E. W BRADFORD, R. M. PARKINS.

a section of a hollow cone and arranged with its point toward the bow of the 

